A toilet sheet for pets (hereinafter referred to as a pet sheet or simply a sheet) such as the one disclosed in Patent Document 1 as shown below has been used to absorb excreta including urine from a household pet such as a dog or a cat. The sheet of Patent Document 1 comprises a liquid permeable topsheet, a liquid impermeable backsheet, and a liquid retentive absorbent member such as an absorbent polymer layer interposed between the two sheets. The pet sheet of this type is usually used as placed on a floor so that a pet animal can urinate on the sheet. The urine is absorbed by the absorptivity of the absorbent member. However, when the animal walks on the sheet having absorbed urine, urine is retransmitted from the absorbent member to the topsheet by the body pressure, which is called “rewet”.
Apart from use of the toilet sheet of the type described, it is known to use pet litter to absorb pet's excreta. For example, Patent Document 2 as shown below proposes cat litter obtained by heat compressing a ground material comprising softwood sawdust into pellets that self-disintegrate on water absorption. The litter is used as spread over a drainboard to an appropriate thickness. On absorbing urine, the litter disintegrates and drops through the drainboard so that only the wetted part of the litter may be disposed of. However, when a large amount of urine is discharged at a time, although most of the urine is absorbed by the litter, the unabsorbed portion of the urine can fall through the drainboard. Therefore, when used in the cat toilet, the litter should be placed in a considerably large quantity. Besides, there is no concept in Patent Document 2 of incorporating the litter into the above-described pet sheet.    Patent Document 1: JP 2003-92940A    Patent Document 2: JP 9-308403A